dogbone resistor value -
murf - 01-26-2014
This may seem like a dumb question for all you Philco techs, but here goes anyway.
Working on a Philco model 118 code 121 chassis and noticed a large dogbone resistor that has a couple hot spots(bubbled).
It is a large dogbone, I am guessing at least 3 watt,with an orange body and red end. No dot in the center.
The schematics does not show this resistor, so I will just replace it with a new one if I can figure out what it is.
Checks about 46.9 k ohms.
Thanks guy's,
murf
RE: dogbone resistor value -
Randy H. - 01-26-2014
Murf,
Well, so far you have described ' 32? '. THe question is what was the DOT. (Body-tip-dot)
If the schematic doesn't show it, what DOES it show at that place in the circuit? Does the radio WORK as it is? Have you tried simply removing it and see if it works that way?
My point is, if the part was not intended to be there, why IS it there. If it came to be as a repair, replaceoing another resistor that failed, and it currently works, I would do one of two tings. (A), I'm lazy. Leave it alone. (B) if some improvement can be had, a good place to start would be 32 K Ohms. Check for heating. If the one that's there gets HOT, there might be a shorted or leaky capacitor on the other end of it. Replacing it with 32 anything might resilt in smoke. BTW... Those resistors were half Watt, one Watt, 2 Watt. The two Watters were BIG. Quarter inch in diameter, and about 2 inches long.
It would help if I knew where it is in the circuit.
Randy.......
RE: dogbone resistor value -
John R - 01-26-2014
Murf,
Believe you are looking at R67; 32K, 2 watts. Cap on output side going to the grids of the 6A7 is probably bad. Therefore, the reason the resistor got hot. John
RE: dogbone resistor value -
murf - 01-26-2014
Well guy's, one end of the resistor is going to the output tranny and the other end to a bakelite block.
Don't see it on the schematics.
No dot that I can see.
I know the electrolitics are bad due to the buzz.
Have not wanted to power it up until the electrolitics are replaced.
Just going by what the previous owner said.
I gather I should start with a 32k and see what happens after I replace the electrolitics.
I noticed there is a can underneath with a 1-1-2 cap installed.
Need to replace these too?
Thanks
murf
RE: dogbone resistor value -
tab10672 - 01-26-2014
B.E.D. Body, end, dot. just in case you run into another one, if there is no dot then it would be the same color as the body. If the body is orange without a dot then the dot is orange also.